This invention relates generally to an agricultural implement, such as an air cart forming part of an air seeding implement for planting seed and fertilizer into the ground, and, more particularly, relates to an interlocking tank compartment structure to hold materials, including fertilizers, seed and herbicides for disposition to the ground.
Air carts for use on agricultural implements are well known Typically, these air carts are used as part of an air seeder in which seeds, fertilizer and herbicides are deposited onto and into the ground during the planting operation. The air carts can be in either two container or three container configuration. Typically, the two container configuration is used to carry a supply of seeds and fertilizer for planting into the ground. The three container configuration can be used to carry an additional element, such as a herbicide, to be deposited on the ground. The three container configuration, however, can also be used to carry only one or two materials in whatever amounts are desired.
Interlocking or nesting the containers through a domed structure that protrudes from one container into a mating impression formed into the body of a second container is known in the art, as demonstrated in U.S. Pat. No. 4,541,549, issued on Sep. 17, 1985. Such domed interlocking structure suffers from an inability to withstand pressures and loads generated from the filing and/or pressurizing of only one of the two tanks. Under such circumstances, the domed structure is known to buckle and, thereby, fail to perform the intended function.
Accordingly, it would be desirable to provide a molded plastic tank structure for an agricultural hopper on an air cart that would be operable under a greater range of uses, including the filling and pressurizing of only one container in the tank structure.